Dannasen said that you should consult with Radagast the Brown. Perhaps he could give mercy to purify the water and provide a chance to redeem the Red-maid.
'The Red-maid's sisters are as wide as the world, for each way the water flows there are River-maidens. To call the Red-maid back to nature thou shalt need to enlist the closest friend to nature, Radagast the Brown.
'The winds tell that he is close by. Perhaps he will find a way to give the land a chance to commune with their mother-sister and let light back into the heart of the Red-maid.'
Radagast is within his tower in the Eglan-camp in Agamaur.
Dannasen instructed you to present the full Urn of Agamaur to Radagast the Brown and ask him to purify the water within so you might restore the Red-maid.
Dannasen is at the Eglan-camp in Agamaur.
You should return to Dannasen and tell him that Radagast has purified the water from Agamaur with a sister's love.